Diversity and Evolution of Mamiellophyceae: Early-Diverging Phytoplanktonic Green Algae Containing Many Cosmopolitan Species

Abstract

The genomic revolution has bridged a gap in our knowledge about the diversity, biology and evolution of unicellular photosynthetic eukaryotes, which bear very few discriminating morphological features among species from the same genus. The high-quality genome resources available in the class Mamiellophyceae (Chlorophyta) have been paramount to estimate species diversity and screen available metagenomic data to assess the biogeography and ecological niches of different species on a global scale. Here we review the current knowledge about the diversity, ecology and evolution of the Mamiellophyceae and the large double-stranded DNA prasinoviruses infecting them, brought by the combination of genomic and metagenomic analyses, including 26 metabarcoding environmental studies, as well as the pan-oceanic GOS and the Tara Oceans expeditions.

Biological and genomic resources for the cosmopolitan phytoplanktonBathycoccus: Insights into genetic diversity and major structural variations

“…Concurrently, sequencing of ITS2 rDNA regions in the Kara sea suggests that a fourth species is yet to be isolated (Belevich et al, 2021) (Figure S2) , highlighting the underestimated taxonomic diversity of the Bathycoccus genus. As reviewed by Yung et al (2022), the description of new species following genome sequencing is frequent in Mamiellophyceae, due to the lack of polymorphism in cellular ultrastructure and in the sequence of rRNA 18S V4 and V9 regions, commonly used as distinguishing characters (Piganeau et al, 2011). While the taxonomic diversity of Bathycoccus sp.…”

“…Among eukaryotic phytoplankton, the class Mamiellophyceae stands out as unicellulars widely distributed in the oceans from poles to equator and marked by seasonal population dynamics in polar and temperate regions (Lambert et al, 2019; Leconte et al, 2020). Mamiellophyceae diverged at the base of the green lineage, making them attractive models for studying essential cellular functions from an evolutionary perspective (Leliaert et al, 2012; Yung et al, 2022). The early whole genome sequencing of Ostreococcus tauri and the implementation of genetic transformation tools, including gene targeting by homologous recombination, have established O. tauri as a model for the study of several cellular pathways such as the circadian clock, the cell division, iron metabolism and vitamin B1 metabolism (Derelle et al, 2006; Corellou et al, 2009; Moulager et al, 2010; O’Neill et al, 2011; Van Oijen et al, 2013; Lozano et al, 2014; Botebol et al, 2015; Paerl et al, 2017; De Barros Dantas et al, 2023).…”

Stimulating and toxic effect of chromium on growth and photosynthesis of a marine chlorophyte

“…It is unclear whether Cr may substitute into some proteins that have certain metabolic functions in phytoplankton, similar to the chemical behaviour of Cd, which can substitute for Zn in some forms of carbonic anhydrase (Price & Morel, 1990). Here, based on previously published data, we further explore the physiological impacts and potential benefits of Cr elevated beyond typical surface open ocean concentrations (c. 2.4 nmol l À1 ; Goring-Harford et al, 2018) on a cosmopolitan marine Chlorophyceae Ostreococcus tauri (Belevich et al, 2021;Yung et al, 2022), by investigating their photosynthesis associated parameters, metallomes, and expressed proteomes.…”

“…Here, based on previously published data, we further explore the physiological impacts and potential benefits of Cr elevated beyond typical surface open ocean concentrations ( c . 2.4 nmol l −1 ; Goring‐Harford et al ., 2018) on a cosmopolitan marine Chlorophyceae Ostreococcus tauri (Belevich et al ., 2021; Yung et al ., 2022), by investigating their photosynthesis associated parameters, metallomes, and expressed proteomes.…”

Genomic characterisation and ecological distribution of Mantoniella tinhauana: a novel Mamiellophycean green alga from the Western Pacific

“…Mamiellophyceae, an early-branching class of photosynthetic picoeukaryotes within the Chlorophyta ( Marin and Melkonian, 2010 ), dominate various ocean regions ( Wang et al, 2019 ; Yung et al, 2022 ), particularly coastal waters ( Lopes dos Santos et al, 2017 ; Tragin and Vaulot, 2018 ). Among the Mamiellophyceae, the order Mamiellales, which includes the families Mamiellaceae and Bathycoccaceae, encompasses the most extensively studied marine Mamiellophyceae genera: Micromonas (Mamiellaceae), Ostreococcus and Bathycoccus (Bathycoccaceae), and more recently, Mantoniella (Mamiellaceae).…”